In multipoint fixed-access wireless communications systems it is common to have a series of basestations distributed across a service area. Each subscriber to such a system has a directional antenna which is focussed on the basestation nearest to it to provide a radio link between the subscriber equipment and the system. The radio links are high frequency links designed through sophisticated link engineering to compensate for RF signal attenuation due to precipitation, attenuation due to foliage, as well as other sources. A disadvantage of such systems is that when a new subscriber is to be connected to the system, a technician is required to visit the subscriber site and manually adjust the directional antenna in order to achieve an acceptable link. Buildings or trees which appear subsequent to an initial manual adjustment of the directional antenna may require subsequent visits by the technician to make further adjustments. This is a very costly approach to establishing and maintaining a link.
Another disadvantage of existing systems is that when a large number of subscribers are located close to a specific basestation, it is possible that the traffic to that basestation will be much larger than the traffic to an adjacent basestation, possibly resulting in congestion.
A further disadvantage of existing systems is that to utilize the full available frequency spectrum at a given basestation, among other complications, entails the use of a combination of frequency hopping, under-provisioning (utilizing less than 100% of the spectrum for simultaneous traffic) and voice activity detection.